dodgy sub

emcb has asked for the wisdom of the Perl Monks concerning the following question:

Hi,

I have written a sub called str_replace. This sub is supposed to work the same as the php function str_replace. Heres the code:

sub str_replace
{
  my( $find,$replace,$what ) = @_;
  $what =~ s/$find/$replace/i;
  return $what;
}

I then use this function to find x and replace it with y in z like so:

$string = str_replace("Hi", "Hello", "Hello My Name Is Elfyn");

This function only returns 'Hi' instead of 'Hi My name Is Elfyn'. Any help on why fellow monks.

Cheers,

Elfyn

Comment on dodgy sub

Replies are listed 'Best First'.
Re: dodgy sub by broquaint (Abbot) on Feb 27, 2002 at 13:42 UTC
Try switching your parameters `print str_replace("Hello", "Hi", "Hello My Name Is Elfyn\n");` [download] Also, since your implmentation of PHP's `str_replace` doesn't take 'mixed' value types (i.e strings, arrays, references etc), it's only a partial implmentation. HTH broquaint	[reply] [d/l]
Re: dodgy sub by strat (Canon) on Feb 27, 2002 at 13:43 UTC
maybe you could try swapping hello and hi? `$string = str_replace("Hello", "Hi", "Hello My Name Is Elfyn");` [download] Besides, if there are strange chars in $find ( \, +, , (, [ or the like), better write: $what =~ s/\Q$find/$replace/; Otherwise, you may get nasty errors Best regards, perl -le "s==F=e=>y~\*martinF~stronat~=>s~[^\w]~~g=>chop,print"	[reply] [d/l]
Re: dodgy sub by dragonchild (Archbishop) on Feb 27, 2002 at 14:55 UTC
Just so you're aware, you can do something like `$string = str_replace(qr/(?:Hello)\|(?:Hi)/, "Good-bye", "Hello My Name + is Elfyn");` [download] qr creates something that allows you to embed regex operators within a string to be used in a regex. :-) ------ We are the carpenters and bricklayers of the Information Age. Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.	[reply] [d/l]
Re: Re: dodgy sub by emcb (Beadle) on Feb 27, 2002 at 15:45 UTC
Thanks oh worthy monks. Im still learning regexps, and i thought my code was wrong. Oh it is :) Elfyn	[reply]